feat: add node replacement UI to Errors Tab (#9253)

## Summary

Adds a node replacement UI to the Errors Tab so users can swap missing
nodes with compatible alternatives directly from the error panel,
without opening a separate dialog.

## Changes

- **What**: New `SwapNodesCard` and `SwapNodeGroupRow` components render
swap groups in the Errors Tab; each group shows the missing node type,
its instances (with locate buttons), and a Replace button. Added
`useMissingNodeScan` composable to scan the graph for missing nodes and
populate `executionErrorStore`. Added `removeMissingNodesByType()` to
`executionErrorStore` so replaced nodes are pruned from the error list
reactively.

## Bug Fixes Found During Implementation

### Bug 1: Replaced nodes render as empty shells until page refresh

`replaceWithMapping()` directly mutates `_nodes[idx]`, bypassing the Vue
rendering pipeline entirely. Because the replacement node reuses the
same ID, `vueNodeData` retains the stale entry from the old placeholder
(`hasErrors: true`, empty widgets/inputs). `graph.setDirtyCanvas()` only
repaints the LiteGraph canvas and has no effect on Vue.

**Fix**: After `replaceWithMapping()`, manually call
`nodeGraph.onNodeAdded?.(newNode)` to trigger `handleNodeAdded` in
`useGraphNodeManager`, which runs `extractVueNodeData(newNode)` and
updates `vueNodeData` correctly. Also added a guard in `handleNodeAdded`
to skip `layoutStore.createNode()` when a layout for the same ID already
exists, preventing a duplicate `spatialIndex.insert()`.

### Bug 2: Missing node error list overwritten by incomplete server
response

Two compounding issues: (A) the server's `missing_node_type` error only
reports the *first* missing node — the old handler parsed this and
called `surfaceMissingNodes([singleNode])`, overwriting the full list
collected at load time. (B) `queuePrompt()` calls `clearAllErrors()`
before the API request; if the subsequent rescan used the stale
`has_errors` flag and found nothing, the missing nodes were permanently
lost.

**Fix**: Created `useMissingNodeScan.ts` which scans
`LiteGraph.registered_node_types` directly (not `has_errors`). The
`missing_node_type` catch block in `app.ts` now calls
`rescanAndSurfaceMissingNodes(this.rootGraph)` instead of parsing the
server's partial response.

## Review Focus

- `handleReplaceNode` removes the group from the store only when
`replaceNodesInPlace` returns at least one replaced node — should we
always clear, or only on full success?
- `useMissingNodeScan` re-scans on every execution-error change; confirm
no performance concerns for large graphs with many subgraphs.


## Screenshots 


https://github.com/user-attachments/assets/78310fc4-0424-4920-b369-cef60a123d50



https://github.com/user-attachments/assets/3d2fd5e1-5e85-4c20-86aa-8bf920e86987



┆Issue is synchronized with this [Notion
page](https://www.notion.so/PR-9253-feat-add-node-replacement-UI-to-Errors-Tab-3136d73d365081718d4ddfd628cb4449)
by [Unito](https://www.unito.io)

src/components/rightSidePanel/errors/SwapNodeGroupRow.vue

@@ -0,0 +1,150 @@
+<template>
+  <div class="flex flex-col w-full mb-4">
+    <!-- Type header row: type name + chevron -->
+    <div class="flex h-8 items-center w-full">
+      <p
+        class="flex-1 min-w-0 text-sm font-medium overflow-hidden text-ellipsis whitespace-nowrap text-foreground"
+      >
+        {{ `${group.type} (${group.nodeTypes.length})` }}
+      </p>
+
+      <Button
+        variant="textonly"
+        size="icon-sm"
+        :class="
+          cn(
+            'size-8 shrink-0 transition-transform duration-200 hover:bg-transparent',
+            { 'rotate-180': expanded }
+          )
+        "
+        :aria-label="
+          expanded
+            ? t('rightSidePanel.missingNodePacks.collapse', 'Collapse')
+            : t('rightSidePanel.missingNodePacks.expand', 'Expand')
+        "
+        @click="toggleExpand"
+      >
+        <i
+          class="icon-[lucide--chevron-down] size-4 text-muted-foreground group-hover:text-base-foreground"
+        />
+      </Button>
+    </div>
+
+    <!-- Sub-labels: individual node instances, each with their own Locate button -->
+    <TransitionCollapse>
+      <div
+        v-if="expanded"
+        class="flex flex-col gap-0.5 pl-2 mb-2 overflow-hidden"
+      >
+        <div
+          v-for="nodeType in group.nodeTypes"
+          :key="getKey(nodeType)"
+          class="flex h-7 items-center"
+        >
+          <span
+            v-if="
+              showNodeIdBadge &&
+              typeof nodeType !== 'string' &&
+              nodeType.nodeId != null
+            "
+            class="shrink-0 rounded-md bg-secondary-background-selected px-2 py-0.5 text-xs font-mono text-muted-foreground font-bold mr-1"
+          >
+            #{{ nodeType.nodeId }}
+          </span>
+          <p class="flex-1 min-w-0 text-xs text-muted-foreground truncate">
+            {{ getLabel(nodeType) }}
+          </p>
+          <Button
+            v-if="typeof nodeType !== 'string' && nodeType.nodeId != null"
+            variant="textonly"
+            size="icon-sm"
+            class="size-6 text-muted-foreground hover:text-base-foreground shrink-0 mr-1"
+            :aria-label="t('rightSidePanel.locateNode', 'Locate Node')"
+            @click="handleLocateNode(nodeType)"
+          >
+            <i class="icon-[lucide--locate] size-3" />
+          </Button>
+        </div>
+      </div>
+    </TransitionCollapse>
+
+    <!-- Description rows: what it is replaced by -->
+    <div class="flex flex-col text-[13px] mb-2 mt-1 px-1 gap-0.5">
+      <span class="text-muted-foreground">{{
+        t('nodeReplacement.willBeReplacedBy', 'This node will be replaced by:')
+      }}</span>
+      <span class="font-bold text-foreground">{{
+        group.newNodeId ?? t('nodeReplacement.unknownNode', 'Unknown')
+      }}</span>
+    </div>
+
+    <!-- Replace Action Button -->
+    <div class="flex items-start w-full pt-1 pb-1">
+      <Button
+        variant="secondary"
+        size="md"
+        class="flex flex-1 w-full"
+        @click="handleReplaceNode"
+      >
+        <i class="icon-[lucide--repeat] size-4 text-foreground shrink-0 mr-1" />
+        <span class="text-sm text-foreground truncate min-w-0">
+          {{ t('nodeReplacement.replaceNode', 'Replace Node') }}
+        </span>
+      </Button>
+    </div>
+  </div>
+</template>
+
+<script setup lang="ts">
+import { ref } from 'vue'
+import { cn } from '@/utils/tailwindUtil'
+import { useI18n } from 'vue-i18n'
+import Button from '@/components/ui/button/Button.vue'
+import TransitionCollapse from '@/components/rightSidePanel/layout/TransitionCollapse.vue'
+import type { MissingNodeType } from '@/types/comfy'
+import type { SwapNodeGroup } from './useErrorGroups'
+import { useNodeReplacement } from '@/platform/nodeReplacement/useNodeReplacement'
+import { useExecutionErrorStore } from '@/stores/executionErrorStore'
+
+const props = defineProps<{
+  group: SwapNodeGroup
+  showNodeIdBadge: boolean
+}>()
+
+const emit = defineEmits<{
+  'locate-node': [nodeId: string]
+}>()
+
+const { t } = useI18n()
+const { replaceNodesInPlace } = useNodeReplacement()
+const executionErrorStore = useExecutionErrorStore()
+
+const expanded = ref(false)
+
+function toggleExpand() {
+  expanded.value = !expanded.value
+}
+
+function getKey(nodeType: MissingNodeType): string {
+  if (typeof nodeType === 'string') return nodeType
+  return nodeType.nodeId != null ? String(nodeType.nodeId) : nodeType.type
+}
+
+function getLabel(nodeType: MissingNodeType): string {
+  return typeof nodeType === 'string' ? nodeType : nodeType.type
+}
+
+function handleLocateNode(nodeType: MissingNodeType) {
+  if (typeof nodeType === 'string') return
+  if (nodeType.nodeId != null) {
+    emit('locate-node', String(nodeType.nodeId))
+  }
+}
+
+function handleReplaceNode() {
+  const replaced = replaceNodesInPlace(props.group.nodeTypes)
+  if (replaced.length > 0) {
+    executionErrorStore.removeMissingNodesByType([props.group.type])
+  }
+}
+</script>

src/components/rightSidePanel/errors/SwapNodesCard.vue

@@ -0,0 +1,38 @@
+<template>
+  <div class="px-4 pb-2 mt-2">
+    <!-- Sub-label: guidance message shown above all swap groups -->
+    <p class="m-0 pb-5 text-sm text-muted-foreground leading-relaxed">
+      {{
+        t(
+          'nodeReplacement.swapNodesGuide',
+          'The following nodes can be automatically replaced with compatible alternatives.'
+        )
+      }}
+    </p>
+    <!-- Group Rows -->
+    <SwapNodeGroupRow
+      v-for="group in swapNodeGroups"
+      :key="group.type"
+      :group="group"
+      :show-node-id-badge="showNodeIdBadge"
+      @locate-node="emit('locate-node', $event)"
+    />
+  </div>
+</template>
+
+<script setup lang="ts">
+import { useI18n } from 'vue-i18n'
+import type { SwapNodeGroup } from './useErrorGroups'
+import SwapNodeGroupRow from './SwapNodeGroupRow.vue'
+
+const { t } = useI18n()
+
+const { swapNodeGroups, showNodeIdBadge } = defineProps<{
+  swapNodeGroups: SwapNodeGroup[]
+  showNodeIdBadge: boolean
+}>()
+
+const emit = defineEmits<{
+  'locate-node': [nodeId: string]
+}>()
+</script>

src/components/rightSidePanel/errors/TabErrors.vue

@@ -27,7 +27,11 @@
           :key="group.title"
           :collapse="collapseState[group.title] ?? false"
           class="border-b border-interface-stroke"
-          :size="group.type === 'missing_node' ? 'lg' : 'default'"
+          :size="
+            group.type === 'missing_node' || group.type === 'swap_nodes'
+              ? 'lg'
+              : 'default'
+          "
           @update:collapse="collapseState[group.title] = $event"
         >
           <template #label>
@@ -40,7 +44,9 @@
                   {{
                     group.type === 'missing_node'
                       ? `${group.title} (${missingPackGroups.length})`
-                      : group.title
+                      : group.type === 'swap_nodes'
+                        ? `${group.title} (${swapNodeGroups.length})`
+                        : group.title
                   }}
                 </span>
                 <span
@@ -69,6 +75,21 @@
                     : t('rightSidePanel.missingNodePacks.installAll')
                 }}
               </Button>
+              <Button
+                v-else-if="group.type === 'swap_nodes'"
+                v-tooltip.top="
+                  t(
+                    'nodeReplacement.replaceAllWarning',
+                    'Replaces all available nodes in this group.'
+                  )
+                "
+                variant="secondary"
+                size="sm"
+                class="shrink-0 mr-2 h-8 rounded-lg text-sm"
+                @click.stop="handleReplaceAll()"
+              >
+                {{ t('nodeReplacement.replaceAll', 'Replace All') }}
+              </Button>
             </div>
           </template>
 
@@ -82,8 +103,16 @@
             @open-manager-info="handleOpenManagerInfo"
           />
 
+          <!-- Swap Nodes -->
+          <SwapNodesCard
+            v-else-if="group.type === 'swap_nodes'"
+            :swap-node-groups="swapNodeGroups"
+            :show-node-id-badge="showNodeIdBadge"
+            @locate-node="handleLocateMissingNode"
+          />
+
           <!-- Execution Errors -->
-          <div v-else class="px-4 space-y-3">
+          <div v-else-if="group.type === 'execution'" class="px-4 space-y-3">
             <ErrorNodeCard
               v-for="card in group.cards"
               :key="card.id"
@@ -150,11 +179,14 @@ import PropertiesAccordionItem from '../layout/PropertiesAccordionItem.vue'
 import FormSearchInput from '@/renderer/extensions/vueNodes/widgets/components/form/FormSearchInput.vue'
 import ErrorNodeCard from './ErrorNodeCard.vue'
 import MissingNodeCard from './MissingNodeCard.vue'
+import SwapNodesCard from './SwapNodesCard.vue'
 import Button from '@/components/ui/button/Button.vue'
 import DotSpinner from '@/components/common/DotSpinner.vue'
 import { usePackInstall } from '@/workbench/extensions/manager/composables/nodePack/usePackInstall'
 import { useMissingNodes } from '@/workbench/extensions/manager/composables/nodePack/useMissingNodes'
 import { useErrorGroups } from './useErrorGroups'
+import { useNodeReplacement } from '@/platform/nodeReplacement/useNodeReplacement'
+import { useExecutionErrorStore } from '@/stores/executionErrorStore'
 
 const { t } = useI18n()
 const { copyToClipboard } = useCopyToClipboard()
@@ -167,6 +199,8 @@ const { shouldShowManagerButtons, shouldShowInstallButton, openManager } =
 const { missingNodePacks } = useMissingNodes()
 const { isInstalling: isInstallingAll, installAllPacks: installAll } =
   usePackInstall(() => missingNodePacks.value)
+const { replaceNodesInPlace } = useNodeReplacement()
+const executionErrorStore = useExecutionErrorStore()
 
 const searchQuery = ref('')
 
@@ -183,7 +217,8 @@ const {
   isSingleNodeSelected,
   errorNodeCache,
   missingNodeCache,
-  missingPackGroups
+  missingPackGroups,
+  swapNodeGroups
 } = useErrorGroups(searchQuery, t)
 
 /**
@@ -229,6 +264,14 @@ function handleOpenManagerInfo(packId: string) {
   }
 }
 
+function handleReplaceAll() {
+  const allNodeTypes = swapNodeGroups.value.flatMap((g) => g.nodeTypes)
+  const replaced = replaceNodesInPlace(allNodeTypes)
+  if (replaced.length > 0) {
+    executionErrorStore.removeMissingNodesByType(replaced)
+  }
+}
+
 function handleEnterSubgraph(nodeId: string) {
   enterSubgraph(nodeId, errorNodeCache.value)
 }

src/components/rightSidePanel/errors/types.ts

@@ -22,3 +22,4 @@ export type ErrorGroup =
       priority: number
     }
   | { type: 'missing_node'; title: string; priority: number }
+  | { type: 'swap_nodes'; title: string; priority: number }

src/components/rightSidePanel/errors/useErrorGroups.ts

@@ -42,6 +42,12 @@ export interface MissingPackGroup {
   isResolving: boolean
 }
 
+export interface SwapNodeGroup {
+  type: string
+  newNodeId: string | undefined
+  nodeTypes: MissingNodeType[]
+}
+
 interface GroupEntry {
   type: 'execution'
   priority: number
@@ -444,6 +450,8 @@ export function useErrorGroups(
     const resolvingKeys = new Set<string | null>()
 
     for (const nodeType of nodeTypes) {
+      if (typeof nodeType !== 'string' && nodeType.isReplaceable) continue
+
       let packId: string | null
 
       if (typeof nodeType === 'string') {
@@ -495,18 +503,53 @@ export function useErrorGroups(
       }))
   })
 
+  const swapNodeGroups = computed<SwapNodeGroup[]>(() => {
+    const nodeTypes = executionErrorStore.missingNodesError?.nodeTypes ?? []
+    const map = new Map<string, SwapNodeGroup>()
+
+    for (const nodeType of nodeTypes) {
+      if (typeof nodeType === 'string' || !nodeType.isReplaceable) continue
+
+      const typeName = nodeType.type
+      const existing = map.get(typeName)
+      if (existing) {
+        existing.nodeTypes.push(nodeType)
+      } else {
+        map.set(typeName, {
+          type: typeName,
+          newNodeId: nodeType.replacement?.new_node_id,
+          nodeTypes: [nodeType]
+        })
+      }
+    }
+
+    return Array.from(map.values()).sort((a, b) => a.type.localeCompare(b.type))
+  })
+
   /** Builds an ErrorGroup from missingNodesError. Returns [] when none present. */
   function buildMissingNodeGroups(): ErrorGroup[] {
     const error = executionErrorStore.missingNodesError
     if (!error) return []
 
-    return [
-      {
+    const groups: ErrorGroup[] = []
+
+    if (swapNodeGroups.value.length > 0) {
+      groups.push({
+        type: 'swap_nodes' as const,
+        title: st('nodeReplacement.swapNodesTitle', 'Swap Nodes'),
+        priority: 0
+      })
+    }
+
+    if (missingPackGroups.value.length > 0) {
+      groups.push({
         type: 'missing_node' as const,
         title: error.message,
-        priority: 0
-      }
-    ]
+        priority: 1
+      })
+    }
+
+    return groups.sort((a, b) => a.priority - b.priority)
   }
 
   const allErrorGroups = computed<ErrorGroup[]>(() => {
@@ -564,6 +607,7 @@ export function useErrorGroups(
     errorNodeCache,
     missingNodeCache,
     groupedErrorMessages,
-    missingPackGroups
+    missingPackGroups,
+    swapNodeGroups
   }
 }